Antioxidant



attests snrrossr es W. Gatw. Nausatuch, com, g, 8 Rubber Company, New

York.

N. E, a corporation of New I This invention relates to improvements inahtioxidants.

An object of the invention is to provide chemicals which may be used perse tor retarding the deterioration of organic substances which tend todeteriorate by absorption of oxygen from the air, such as rubber orallied gums, artificial rubber-like materials, such as neoprene(polychloroprene), and buns (polyoleflnes) unsaturated fatty oils suchas unsatin'ated vegetable oils, essential oils, petroleum oils and theirderivatives, such as gasoline, soaps, aldehydes, paints, and the like.Another object is to provide a class of rubber antioxidants whichpreserve light or white rur goods with a minimum discoloration duringFurther objects will be apparent from the following description.

According to the invention, the organic substance has incorporatedtherein a chemical having the proble general formula (Ho)::R-

(NH=SO:R')a where :2: represents a whole number which may be one ormore; R is an ammatic nucleus; R. is an alltyl or aryl group; and nrepts a whole number which may be one or more.

Thematerials are called sulfonyl amino phenols, the word "phenols" beinghere given a broad meaning to include the sulionyl amino naphthols. Theproducts are. in general, lightcolored crystalline chemicals havingpractically no odor and they can be easily incorporated into rubber.

The following equation is illustrative of the usual preparation ofchemicals 01 this type. Other methods may be used however to preparethese chemicals.

p-Aminophenol m-Aminophenol o-Aminophenol 2, -diaminophenol ApplicationJan 3, 1942,

Serial Non-425,575

(on. etc-sot) 5-1- i l-naphthol 2-oresorcinol 1,6-diamino-2-nsphthol2,4- t w oresorcinol z-amino-fi-hydroxytoluene 3,5-diamino-o-cresol.

- penyl, methallyloxy, butylamino, mercapto, etc.

Examples of the suli'onyl chlorides are as follows: p-toluene sulionchloride, benzene sulion sulion chloride, methyl suli'on chloride, etc.

The following examples are given in support of the. invention, but areto be understood as illustrative only and not limiting thereof:

Exenrtsl.

2,4-diaminophenol dihydrochloride (40 grams) is slurried in 95% ethylalcohol (230 grams) at 53 C. A sodium acetate solution containing 125grams of sodium-acetate trihydrate in grams of water is added at 53 C.with stirring. The crystalline p-toluene-suli'onchloride (80 grams) isadded to the agitated mixture. During the addition the temperature risesfrom 53 C. to C. The reaction mass is maintained at 65-70 C. for

two hours, and then allowed to cool to room temperature. The reactionmixture is filtered, the

precipitate washed free of chlorides, and then recrystallized frommethanol. 'The yield is excellent. The product is named2,4-(p-toluenesulfonylamino) phenol Nn-sor-Ocm Nn-soOcni The meltingrange of the 2,4- (p-toluenesu lionylamino) phenol as prepared shove 287C. It is aseaeoo a white, odorless, crystalline Found Theory I FoundTheory Percent nitrogen 4.35 4- 47 I 5 Per cent SlflfllL; 10.03 10.25

Per cent nitrogen 0.40 6.50 (I I I I 14-79 The effectiveness. of thematerials is shown Exmrm: 2'

This chemical is prepared'as in Example 1 from o-aminophenoi (25 grams),sodium acetate tri- 1 hydrate (35 grams), and p-toluenesulionchlorideThe compound melts at 142.5 C.

('70 grams).

and is a white crystallineniaterial. It is namedo-(p-toluenesulfonylamino) phenol j on l 1,13 3 iihis"chemicalisprepared 83in Example 1 from p -aminophenol"(25- grarnshsodlum acetatetrihydrate (35 grams), and'naphthalene beta sulfonyi chloride (52grams). The compound melts at 167-479 C. and is a light browncrystalline product. It is named p-(bcta-naphthalenesuh' fonylamino)phenol E a l Found Theory 7 Percent-nitrogen -L '00s 4.08Percenteuliur-.. 10.50 10.70

I the chemical is prepared as in (Example 1 from p-aminophenol (100grams), sodium acetate trihydratell'io grams), and p-toluenesulvi'onchloride: (280 s'rams).--'=The compound is a white crystallinematerial melting at 148.5 C. It is named p-(p-toluenesulionylamino)phenol "Exam n and p-toluenesulionchloride (30 grams). The compound islight brown in color andmelts at 188.5 .C.,. It is named5-(p-to1uenesuli'ony1- aminol-i-naphtholj v cm-O-aor-Nn below. whentested in a white molded rubber compound of the following composition,the parts l0 being by weight:

Master batch Bale crep 100.00 Zinc oxide 10.00

N Lithopone 60.00 Whiting -3. 60.00 Zinc soap of cocoanut 'oil fattyacids"--- 0.50 'Bulfur 3.00 Tetramethyl thiuram monosulfide 0.15

The antioxidant to be tested was incorporated a in the ratio of one(1.0) port to one hundred (100) parts of pale crepe. Cures were made for26 10, 20,, and 30 minutes at 30 pounds per square inch steam pressure.

The following data shows the tensile in pounds per square inch andpercent elongation at break (before and after aging 96 hours inoxygenbomb 30 under 300 pounds pressure and at 70 C.

2,-1-(p-to1uenesulfonyl- .Cure at 30 lbs. Control amino) phenol w UNAGED1111118 2, 600-736 2, 600-730 2) mins'. 2, 520-733 2. 400-710 on mins 2,160-726 2,,000-090 e0 AGED 10 mins 1, 700-703 2, 000-723 1) mins 400-3661, 740-690 mins 1,330-076 Cure at 30 lbs Control O'W'tQIueDeSUHOHYI' aamino) phenol UNAGEl) AGED 1, 700-703 1, 750r-7fi) 400-200 1, 300-090800-050 p-(beta-na hthalene- 09mm] sulfonylami no) phenol UNAGED p-(ptoluene Control sulionyiemino) phenol :,sac-ns I 1'1! 2, zoo-01s AGED -dip-toluene- (June at 30 lbs Control suiionylominmi-naphthcl rmaoun mins2, scc- 2, B00463 so mics 8, 200-740 2, W746 80 mins 1.800410 Kim-710AGED 10 m 1. 840-132 min: l, Mil-7m l Failed. '1.

This class oi antiomdants is almost completely non-discoloring to rubberstock.' to white cloth, and to lacquered tape in contact with the rubberstock alter nine-day exposures to sunlight through gl. Mmt commercialantioxidants under the same conditions cause considerabiedis,coloration.

It is to be unde that the invention may be applied to the preservationoi natural rubber compositions well as artificially prepared rubberctions including reclaimed rubbers and latices of such. rubbercompositions.

It is also to be undo that other desired filling and ingredients may beincorporated along with the preservativefor example in the c oi rubberthere may be incorporated other accelerators, softeners, etc- Theti-oxit may be incorporated in any yp oi rubber comition such as those,used for automobile tires and tubes, hose, belting. sheets and threadrubber, rubberized fabrics, molded goods, and shoes, etc., ,wherevulcanized in a mold, in open steam, in hot air, or in the cold by theso called acid process. The proportion of the antioxidant may i w from2. A method oi preserving organic substances which tend to deteriorateby absorption 0! oxygen from the air "which comprises incorporatingtherein an antioxidant which is an aminophenol having nitrogen of theamino group Joined to a sulfonyi radical which is in turn Joined to ahydrocn group.

3. A method oi preserving organic suces which tend to deteriorate byabsorption of oxygen from the air which comprises incorporating thereinan antioxidant consisting of a compound having the general formula wherea is a whole number; R is an aromatic nucleus; HO refers to a phenolichgdroxy radical, R. is a radical selected from the class consist ing oralkyl and aryl radicals; and n represents a whole number.

' 4. Amethod which comprises incorporating in a rubber composition anantiomdant which is a sulphonyi amino phenol, in which the suiphcnyigroup is attached to the phenol group through the l. group.

5. A method which comprises incorporating in a rubber composition. anantioxidant which is an aminophenol having nitrogen of the amino groupcontaining an antioxidant which is a sulphonyl about 6.1% to 5%.,although either smaller or greater proportions y be found useful. If thematerial to which. it. is added is a liquid such as rubber cement or anoil, the antioxidant may be dissolved there in a suitable smallproportion. The antioxidant may be incorporated into solid substances bymilling or mastication and prepared for incorporation into dispersionsor solutions either in powder, paste, or solution form, or applie?! insuch to for incorporation by diflusionto the surfaces oi vuic canizedrubbers f Having thus des'c' bed my invention, what I claimant! desireto protect by Letters Patent is:

1. A. method of preserving organic substances which tend to deteriorateby absorption of oxy'-= gen irom the air which comprises incorporatingtherein an antioxidant which is a suiionyl amino phenol, in which theshlphonyi group is to the phenol through the or unvoi- 1 ttached m aminophenol, in whichthe sulphonyl group is attached to the phenol groupthrough the amino group.

he. rubber composition containing an antioxidant which is a suiphonylamino phenol. in which the sulphonyl group is attached to the phenolgroup through the o group.

8. An organic substance which tendsto deteriorate by absorption oioxygen from the air containing' an antioxidant which is a toluenesulphonyl amino phenol, in which the sulphonyi group is attached to thephenol group through the amino group.

9. An organic substance which tends to deteriorate by absorption ofoxygen from the air containing an antioxidant which is2,4-(p-toluenesulionviamino) phenol. I

10. An organic substance which tends to deteriorateby absorption ofoxygen from the air containing an antioxidant which is anaphthalenesulphonyl amino phenol, in which the suiphonyl group isattached to the phenol group through enemas w. Game.

